3rd generation partnership project (3GPP) long-term evolution (LTE) is a technology for enabling high-speed packet communications. Many schemes have been proposed for the LTE objective including those that aim to reduce user and provider costs, improve service quality, and expand and improve coverage and system capacity. The 3GPP LTE requires reduced cost per bit, increased service availability, flexible use of a frequency band, a simple structure, an open interface, and adequate power con-sumption of a terminal as an upper-level requirement.
Recently, there has been an interest to ensure that the public has the capability to receive timely and accurate alerts, warnings and critical information regarding disasters and other emergencies irrespective of what communications technologies they use. As has been learned from disasters such as earthquakes, tsunamis, hurricanes and wild fires, such a capability is essential to enable the public to take appropriate action to protect their families and themselves from serious injury, or loss of life or property. This interest to enhance the reliability, resiliency, and security of warning notifications to the public by providing a mechanism to distribute warning notifications over 3GPP systems is the impetus for a public warning system (PWS).
Under certain circumstances, it will be desirable to prevent user equipment (UE) users from making access attempts (including emergency call attempts) or responding to pages in specified areas of a public land mobile network (PLMN). Such situations may arise during states of emergency, or where 1 of 2 or more co-located PLMNs has failed. Broadcast messages should be available on a cell by cell basis indicating the class(es) or categories of subscribers barred from network access. The use of these fa-cilities allows the network operator to prevent overload of the access channel under critical conditions. It is not intended that access control be used under normal operating conditions. It should be possible to differentiate access control between circuit-switched (CS) and packet-switched (PS) domains.
Various access control schemes may be defined in 3GPP LTE, which may include access class barring (ACB), extended access barring (EAB), service specific access control (SSAC), and application specific congestion control for data communication (ACDC). A method for performing access control for public safety and/or mission critical push to talk (MCPTT) may be required.